/*
 * Wi-Fi Protected Setup
 * Copyright (c) 2007-2008, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#include "common.h"
#include "wps_i.h"
#include "wps_dev_attr.h"
#include "ieee802_11_defs.h"


/**
 * wps_init - Initialize WPS Registration protocol data
 * @cfg: WPS configuration
 * Returns: Pointer to allocated data or %NULL on failure
 *
 * This function is used to initialize WPS data for a registration protocol
 * instance (i.e., each run of registration protocol as a Registrar of
 * Enrollee. The caller is responsible for freeing this data after the
 * registration run has been completed by calling wps_deinit().
 */
struct wps_data * wps_init(const struct wps_config *cfg)
{
        struct wps_data *data = os_zalloc(sizeof(*data));
        if (data == NULL)
                return NULL;
        data->wps = cfg->wps;
        data->registrar = cfg->registrar;
        if (cfg->registrar) {
                os_memcpy(data->uuid_r, cfg->wps->uuid, WPS_UUID_LEN);
        } else {
                os_memcpy(data->mac_addr_e, cfg->wps->dev.mac_addr, ETH_ALEN);
                os_memcpy(data->uuid_e, cfg->wps->uuid, WPS_UUID_LEN);
        }
        if (cfg->pin) {
                data->dev_pw_id = DEV_PW_DEFAULT;
                data->dev_password = os_malloc(cfg->pin_len);
                if (data->dev_password == NULL) {
                        os_free(data);
                        return NULL;
                }
                os_memcpy(data->dev_password, cfg->pin, cfg->pin_len);
                data->dev_password_len = cfg->pin_len;
        }

        data->pbc = cfg->pbc;
        if (cfg->pbc) {
                /* Use special PIN '00000000' for PBC */
                data->dev_pw_id = DEV_PW_PUSHBUTTON;
                os_free(data->dev_password);
                data->dev_password = os_malloc(8);
                if (data->dev_password == NULL) {
                        os_free(data);
                        return NULL;
                }
                os_memset(data->dev_password, '0', 8);
                data->dev_password_len = 8;
        }

        data->state = data->registrar ? RECV_M1 : SEND_M1;

        if (cfg->assoc_wps_ie) {
                struct wps_parse_attr attr;
                wpa_hexdump_buf(MSG_DEBUG, "WPS: WPS IE from (Re)AssocReq",
                                cfg->assoc_wps_ie);
                if (wps_parse_msg(cfg->assoc_wps_ie, &attr) < 0) {
                        wpa_printf(MSG_DEBUG, "WPS: Failed to parse WPS IE "
                                   "from (Re)AssocReq");
                } else if (attr.request_type == NULL) {
                        wpa_printf(MSG_DEBUG, "WPS: No Request Type attribute "
                                   "in (Re)AssocReq WPS IE");
                } else {
                        wpa_printf(MSG_DEBUG, "WPS: Request Type (from WPS IE "
                                   "in (Re)AssocReq WPS IE): %d",
                                   *attr.request_type);
                        data->request_type = *attr.request_type;
                }
        }

        return data;
}


/**
 * wps_deinit - Deinitialize WPS Registration protocol data
 * @data: WPS Registration protocol data from wps_init()
 */
void wps_deinit(struct wps_data *data)
{
        if (data->wps_pin_revealed) {
                wpa_printf(MSG_DEBUG, "WPS: Full PIN information revealed and "
                           "negotiation failed");
                if (data->registrar)
                        wps_registrar_invalidate_pin(data->wps->registrar,
                                                     data->uuid_e);
        } else if (data->registrar)
                wps_registrar_unlock_pin(data->wps->registrar, data->uuid_e);

        wpabuf_free(data->dh_privkey);
        wpabuf_free(data->dh_pubkey_e);
        wpabuf_free(data->dh_pubkey_r);
        wpabuf_free(data->last_msg);
        os_free(data->dev_password);
        os_free(data->new_psk);
        wps_device_data_free(&data->peer_dev);
        os_free(data);
}


/**
 * wps_process_msg - Process a WPS message
 * @wps: WPS Registration protocol data from wps_init()
 * @op_code: Message OP Code
 * @msg: Message data
 * Returns: Processing result
 *
 * This function is used to process WPS messages with OP Codes WSC_ACK,
 * WSC_NACK, WSC_MSG, and WSC_Done. The caller (e.g., EAP server/peer) is
 * responsible for reassembling the messages before calling this function.
 * Response to this message is built by calling wps_get_msg().
 */
enum wps_process_res wps_process_msg(struct wps_data *wps,
                                     enum wsc_op_code op_code,
                                     const struct wpabuf *msg)
{
        if (wps->registrar)
                return wps_registrar_process_msg(wps, op_code, msg);
        else
                return wps_enrollee_process_msg(wps, op_code, msg);
}


/**
 * wps_get_msg - Build a WPS message
 * @wps: WPS Registration protocol data from wps_init()
 * @op_code: Buffer for returning message OP Code
 * Returns: The generated WPS message or %NULL on failure
 *
 * This function is used to build a response to a message processed by calling
 * wps_process_msg(). The caller is responsible for freeing the buffer.
 */
struct wpabuf * wps_get_msg(struct wps_data *wps, enum wsc_op_code *op_code)
{
        if (wps->registrar)
                return wps_registrar_get_msg(wps, op_code);
        else
                return wps_enrollee_get_msg(wps, op_code);
}


/**
 * wps_is_selected_pbc_registrar - Check whether WPS IE indicates active PBC
 * @msg: WPS IE contents from Beacon or Probe Response frame
 * Returns: 1 if PBC Registrar is active, 0 if not
 */
int wps_is_selected_pbc_registrar(const struct wpabuf *msg)
{
        struct wps_parse_attr attr;

        /*
         * In theory, this could also verify that attr.sel_reg_config_methods
         * includes WPS_CONFIG_PUSHBUTTON, but some deployed AP implementations
         * do not set Selected Registrar Config Methods attribute properly, so
         * it is safer to just use Device Password ID here.
         */

        if (wps_parse_msg(msg, &attr) < 0 ||
            !attr.selected_registrar || *attr.selected_registrar == 0 ||
            !attr.dev_password_id ||
            WPA_GET_BE16(attr.dev_password_id) != DEV_PW_PUSHBUTTON)
                return 0;

        return 1;
}


/**
 * wps_is_selected_pin_registrar - Check whether WPS IE indicates active PIN
 * @msg: WPS IE contents from Beacon or Probe Response frame
 * Returns: 1 if PIN Registrar is active, 0 if not
 */
int wps_is_selected_pin_registrar(const struct wpabuf *msg)
{
        struct wps_parse_attr attr;

        /*
         * In theory, this could also verify that attr.sel_reg_config_methods
         * includes WPS_CONFIG_LABEL, WPS_CONFIG_DISPLAY, or WPS_CONFIG_KEYPAD,
         * but some deployed AP implementations do not set Selected Registrar
         * Config Methods attribute properly, so it is safer to just use
         * Device Password ID here.
         */

        if (wps_parse_msg(msg, &attr) < 0)
                return 0;

        if (!attr.selected_registrar || *attr.selected_registrar == 0)
                return 0;

        if (attr.dev_password_id != NULL &&
            WPA_GET_BE16(attr.dev_password_id) == DEV_PW_PUSHBUTTON)
                return 0;

        return 1;
}


/**
 * wps_get_uuid_e - Get UUID-E from WPS IE
 * @msg: WPS IE contents from Beacon or Probe Response frame
 * Returns: Pointer to UUID-E or %NULL if not included
 *
 * The returned pointer is to the msg contents and it remains valid only as
 * long as the msg buffer is valid.
 */
const u8 * wps_get_uuid_e(const struct wpabuf *msg)
{
        struct wps_parse_attr attr;

        if (wps_parse_msg(msg, &attr) < 0)
                return NULL;
        return attr.uuid_e;
}


/**
 * wps_build_assoc_req_ie - Build WPS IE for (Re)Association Request
 * @req_type: Value for Request Type attribute
 * Returns: WPS IE or %NULL on failure
 *
 * The caller is responsible for freeing the buffer.
 */
struct wpabuf * wps_build_assoc_req_ie(enum wps_request_type req_type)
{
        struct wpabuf *ie;
        u8 *len;

        wpa_printf(MSG_DEBUG, "WPS: Building WPS IE for (Re)Association "
                   "Request");
        ie = wpabuf_alloc(100);
        if (ie == NULL)
                return NULL;

        wpabuf_put_u8(ie, WLAN_EID_VENDOR_SPECIFIC);
        len = wpabuf_put(ie, 1);
        wpabuf_put_be32(ie, WPS_DEV_OUI_WFA);

        if (wps_build_version(ie) ||
            wps_build_req_type(ie, req_type)) {
                wpabuf_free(ie);
                return NULL;
        }

        *len = wpabuf_len(ie) - 2;

        return ie;
}


/**
 * wps_build_probe_req_ie - Build WPS IE for Probe Request
 * @pbc: Whether searching for PBC mode APs
 * @dev: Device attributes
 * @uuid: Own UUID
 * @req_type: Value for Request Type attribute
 * Returns: WPS IE or %NULL on failure
 *
 * The caller is responsible for freeing the buffer.
 */
struct wpabuf * wps_build_probe_req_ie(int pbc, struct wps_device_data *dev,
                                       const u8 *uuid,
                                       enum wps_request_type req_type)
{
        struct wpabuf *ie;
        u8 *len;
        u16 methods;

        wpa_printf(MSG_DEBUG, "WPS: Building WPS IE for Probe Request");

        ie = wpabuf_alloc(200);
        if (ie == NULL)
                return NULL;

        wpabuf_put_u8(ie, WLAN_EID_VENDOR_SPECIFIC);
        len = wpabuf_put(ie, 1);
        wpabuf_put_be32(ie, WPS_DEV_OUI_WFA);

        if (pbc)
                methods = WPS_CONFIG_PUSHBUTTON;
        else
                methods = WPS_CONFIG_LABEL | WPS_CONFIG_DISPLAY |
                        WPS_CONFIG_KEYPAD;

        if (wps_build_version(ie) ||
            wps_build_req_type(ie, req_type) ||
            wps_build_config_methods(ie, methods) ||
            wps_build_uuid_e(ie, uuid) ||
            wps_build_primary_dev_type(dev, ie) ||
            wps_build_rf_bands(dev, ie) ||
            wps_build_assoc_state(NULL, ie) ||
            wps_build_config_error(ie, WPS_CFG_NO_ERROR) ||
            wps_build_dev_password_id(ie, pbc ? DEV_PW_PUSHBUTTON :
                                      DEV_PW_DEFAULT)) {
                wpabuf_free(ie);
                return NULL;
        }

        *len = wpabuf_len(ie) - 2;

        return ie;
}


void wps_free_pending_msgs(struct upnp_pending_message *msgs)
{
        struct upnp_pending_message *p, *prev;
        p = msgs;
        while (p) {
                prev = p;
                p = p->next;
                wpabuf_free(prev->msg);
                os_free(prev);
        }
}
